1. Field of the Invention
The present invention relates generally to the weaving of textiles and, in particular, to a quick change kit for a fluid jet weaving loom.
2. Description of the Related Art
In the current state of the art of weaving textiles, there are two types of jet looms: air and water. In water jet weaving looms, there are two types of picking apparatuses: single pick and so-called "pick and pick". "Picking" may be defined as the operation of passing a "pick", i.e. a filling yarn, through a warp shed during the weaving process on the loom. The "pick" may be more specifically defined as a single filling thread shot by the water jet through the warp shed which extends across the loom. The picks or filling yarns are interlaced with the warp ends to form a woven fabric. See "Man-Made Fiber and Textile Dictionary" (3rd Ed. 1974) at pp. 81-82.
The single pick unit is used for particularly simple woven fabric styles. The pick and pick unit is used for more complex woven fabric styles using either one or two different types of filling yarns. Whenever a weaver has wanted to change a loom from producing a style of fabric with a single pick unit to producing a different, more fanciful style of fabric with a pick and pick unit (or vice versa), about 18 man-hours of work have been required to make the conversion because, either way, the entire pick insertion unit must be removed from the loom and replaced with the other unit. This amount of down time is deemed severe.
In FIG. 1 of the drawings, the single pick unit 10 of the prior art is illustrated. More particularly, the unit 10 is a Nissan water jet loom, as are all the other looms illustrated herein. The yarn 12 is drawn from a supply package 14 directly to a feed roll 16. The amount of yarn 12 that is wrapped around the feed roll 16 is determined by a measuring drum 18. The measuring drum 18 drives the feed roll 16 by contacting a shaft 26 which rotates the feed roll 16. In order to change the amount of the yarn 12 to be wrapped around the feed roll 16, the weaver merely changes the measuring drum 18, which comes in various sizes, with different diameters to vary the amount of the yarn 12 to be wrapped per revolution. The amount of yarn 12 that the weaver selects to be measured by the drum 18 is the length of yarn 12 that is needed to travel across a shed 50 of warp yarns 52. Drum 18 is rotated on a shaft 20A that is controlled by a first gear 22A. A larger gear 22B is the main gear driven by the loom itself through a shaft 20B. A smaller gear 22C is driven by the larger gear 22B through a timing belt 24. This smaller gear 22C, in turn, drives the single pick unit 10 through a shaft 20C.
After being wrapped around the feed roll 16, the measured amount of yarn 12 is blown down a tube 28 by a blower 30 operated by a motor 32. The tube 28 has a longitudinal slot 29 extending along its length a distance of about the same length as the measured amount of yarn 12. The yarn 12 extends out the far end of the tube 28. The return of the yarn 12 through a plurality of guides 34A, 34B, and 34C to a gripper 36 is controlled by a gripper arm 38. The gripper 36 holds the yarn 12 until a reed (not shown) swings through the shed 50 of warp yarns 52. A water jet nozzle 40 is positioned to shoot the measured amount of yarn 12, i.e. a single pick, across the shed 50 of the loom. When the nozzle 40 is ready to shoot the pick in a jet stream of water 42, the gripper arm 38 raises the gripper 36 so that the yarn 12 is released and the leading end of the measured amount of yarn 12 is shot across the shed 50 until it reaches the other side (not shown) of the loom. This shooting pays out the yarn 12 from the tube 28 through slot 29. When the measured amount of yarn 12 is paid out passed gripper 36, the gripper arm 38 lowers gripper 36 onto the trailing end of the measured amount of yarn 12 and holds the yarn 12 until a cutter (not shown) cuts the yarn 12 off between nozzle 40 and warp yarns 52. As the measured amount of yarn 12 is shot across the shed 50 by the nozzle 40, a second measured amount of yarn 12 is delivered from drum 16 to the tube 28 and a third measured amount of yarn 12 is measured by the drum 18. The interactions of these various elements are synchronized by a computer (not shown). As can be seen, in the single pick unit 10, three measured amounts of yarn 12 are being handled simultaneously.
FIG. 2 of the drawings depicts the "pick and pick" unit 100, so called because it handles two different "picks" or filling yarns 112 and 112', which may be either the same or diverse yarns, at the same time. This is a perspective view from an angle different than the angle of FIG. 1.
The yarns 112 and 112' are drawn from supply packages 114 and pass through fixed eyelets 116 and 116' into hollow tubes 118 and 118', respectively. After passing out of the tubes 118 and 118', the yarns 112 and 112' are diverted at an angle directly to first guides 120 and 120' which are secured to winding arms 122 and 122' that are, in turn, mounted on shafts 124 and 124', respectively. The shafts 124 and 124' rotate the winding arms 122 and 122' so that the yarns 112 and 112' are caused to be wrapped around stationary measuring drums 126 and 126'. The amounts of yarns 112 and 112' that are wrapped around the measuring drums 126 and 126', respectively, are predetermined by the winding arms 122 and 122' which typically make four turns around the drums 126 and 126'.
A lower gear 144 is driven by the loom through a shaft 146 while an upper gear 144' is driven by the lower gear 144 through a timing belt 147 so that the upper gear 144' may, in turn, drive the pick and pick unit 100. The elements inside the pick and pick unit 100 for connection to the measuring drums 126 and 126' are omitted for the sake of simplicity since such elements are conventional. The amounts of the yarns 112 and 112' which have been measured and wrapped around the drums 126 and 126' by the arms 122 and 122' then pass off the drums 126 and 126' and out through second guides 130 and 130'. From the guides 130 and 130', the yarns 112 and 112' are drawn under protective covers 132 and 132' through third guides 134 and 134' and adjustable fourth guides 136 and 136' to grippers 128 and 128'. The grippers 128 and 128' are controlled by gripper arms 138 and 138', respectively. The grippers 128 and 128' hold the yarns 112 and 112' until a reed (not shown) swings through the shed 150 of warp yarns 152. Water jet nozzles 140 and 140' are positioned to alternately project the measured amounts of yarns 112 and 112', i.e. a pick of yarn 112 and then a pick of yarn 112', across a shed 150 of the loom. This alternating operation is controlled by a switching valve (not shown) supplying water to the jet nozzles 140 and 140'.
When the nozzle 140 is ready to project the measured amount of yarn 112 in a jet stream of water 142, the gripper arm 138 raises the gripper 128 so that the measured amount of yarn 112 is released through a fifth guide 145 while the gripper arm 138' holds the gripper 128' down so that the measured amount of yarn 112' is retained. The leading end of the measured amount of yarn 112 is projected across the shed 150 until it reaches the other side (not shown) of the loom after paying off from drum 126. When the measured amount of yarn 112 is paid out, the gripper 128 comes down and closes on the trailing end of the measured amount of yarn 112 and holds it until a cutter (not shown) cuts the yarn 112 between nozzle 140 and warp yarns 152. After the measured amount of yarn 112 is cut off, the gripper arm 138' raises the gripper 128' so that the measured amount of yarn 112' is released through the fifth guide 145 and is projected by the nozzle 140' in a water jet stream 142' across the shed 150.
Two disadvantages of the prior art single pick unit 10 shown in FIG. 1 are that the motor 32, the blower 30, and the tube 28 take up space and require energy to operate, thus reducing the efficiency of the single pick unit 10.
Although the prior art pick and pick unit 100 shown in FIG. 2 does not require the motor 32, the blower 30, and the tube 28 for operational purposes, it is a major disadvantage that it takes about 18 man-hours to disconnect and replace the pick and pick unit 100 with the single pick unit 10 whenever a styling change must be made on the loom in order to produce a woven fabric by the single pick unit 10 because such woven fabric cannot be manufactured by the pick and pick unit 100.